Controllable electrical outlet with a controlled wired output

ABSTRACT

A load control system having a controllable electrical outlet provides a low cost solution for controlling a plurality of standard electrical outlets. The controllable electrical outlet may be coupled in series between a power source and at least one standard electrical outlet for controlling the power delivered to the standard electrical outlet. The controllable electrical outlet may comprise an actuator for allowing the controllable electrical outlet to be associated with an input device for receiving digital messages from the input device. The controllable electrical outlet may be installed in a standard electrical wallbox, e.g., replacing a previously-installed standard electrical outlet. The actuator may be easily accessed to associate the controllable electrical outlet with the input device and a radio-frequency receiver and antenna may be located in the controllable electrical outlet to provide optimum reception of radio-frequency signals.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to commonly-assigned U.S. ProvisionalApplication No. 61/946,127, filed Feb. 28, 2014, entitled CONTROLLABLEELECTRICAL OUTLET WITH A CONTROLLED WIRED OUTPUT, the entire disclosureof which is hereby incorporated by reference.

BACKGROUND

Field of the Disclosure

The present disclosure relates to a load control system for controllingthe power delivered to one or more electrical loads, and moreparticularly, to a load control system comprising a controllableelectrical outlet having a controlled wired output for controlling thepower delivered to outlets of other electrical outlets and thuselectrical loads connected to those outlets.

Description of the Related Art

Many consumers reduce the total cost of electrical energy by reducingthe total energy usages of electrical loads, such as lighting loads. Forexample, lighting loads are often controlled in response to occupancyand vacancy sensors, which detect occupancy and/or vacancy conditions ina space, to save energy. Typically, the lighting loads are turned onwhen the space is occupied and turned off when the space is unoccupied.In addition, consumers are becoming more sensitive to the amount ofenergy consumed by electrical loads, such as plug-in electrical loadsthat are plugged into electrical receptacles. Such plug-in electricalloads may still consume energy to maintain a standby mode when “turnedoff” and are often referred to as “vampire” loads. Some standards (suchas ASHRAE 90.1 and California Title 24) are now requiring that manyelectrical outlets installed in new construction or major renovationsmust be controlled (e.g., switched) to provide energy savings. Forexample, the electrical outlets may be controlled in response to atimeclock and/or an occupancy or vacancy sensor.

Some prior art systems for controlling (e.g., switching) electricaloutlets include load control devices that may be remotely-located, forexample, out of view above a ceiling of a room, behind a wall of a room,or in a remote electrical closet. Installation of these prior artsystems may be complicated since electrical wires need to be run fromthe remotely-located load control devices to the electrical outlets. Theload control devices may be responsive to input devices (e.g., wirelesstransmitters), such as timeclocks and/or an occupancy or vacancysensors. However, to program the load control device to be responsive tothe input devices, the remotely-located load control devices must beaccessed (e.g., to press a button on the load control device), whichincreases the time (and thus the cost) required to program the systemsince the load control device is remotely located from the inputdevices. Further, the need to have an additional load control device forcontrolling the electrical outlets adds cost to the load control system.

Some prior art electrical outlets are configured to directly receivewireless signals, e.g., radio-frequency (RF) signals, such that anadditional remotely-located load control device is not required tocontrol the electrical outlets. However, these RF-responsive electricaloutlets cost more than a standard electrical outlet. In order to providecontrol of most of the electrical outlets in a building, anRF-responsive electrical outlet must be installed in each and everywallbox where control of plug-in electrical loads is desired, whichgreatly adds to the cost of the load control system.

SUMMARY

As described herein, a load control system having a controllableelectrical outlet may provide a low cost solution for controlling aplurality of standard electrical outlets. The load control system maynot require any additional electrical devices (e.g., other than thecontrollable electrical outlet) to control the standard electricaloutlets, which for example, may make it simple to install. Thecontrollable electrical outlet may be coupled in series between a powersource and at least one standard electrical outlet for controlling thepower delivered to the standard electrical outlet. The controllableelectrical outlet may comprise one or more of: (1) at least oneelectrical receptacle adapted to receive a plug of a plug-in electricalload; (2) a first electrical connection adapted to be electricallycoupled to the power source for receiving a hot voltage for powering theelectrical load; (3) a second electrical connection adapted to beelectrically coupled to the standard electrical outlet; (4) a loadcontrol circuit coupled in series electrical connection between thefirst and second electrical connections for controlling the powerdelivered to the standard electrical outlet; (5) a communication circuitfor receiving a digital message; or (6) a digital control circuitcoupled to the load control circuit and the communication circuit forcontrolling the power delivered to the standard electrical outlet inresponse to the digital message received via the communication circuit.

The controllable electrical outlet may also comprise one or moreactuators. An actuator may provide a user interface for configuring thecontrollable electrical outlet. For example, an actuator may be used toassociate the controllable electrical outlet with an input device (e.g.,a radio-frequency (RF) transmitter), such that the communication circuitis able to receive the digital message from the input device. Thecontrollable electrical outlet may be installed in a standard electricalwallbox, e.g., replacing a previously-installed standard electricaloutlet. The actuator may be located on an exterior face of thecontrollable electrical outlet, for example, such that it may be easilyaccessed to associate the controllable electrical outlet with the inputdevice thus simplifying configuration of the load control system. Thecommunication circuit (e.g., an RF receiver and antenna) may be locatedin the controllable electrical outlet (e.g., in the same room as aninput device), for example, to provide optimum reception of wirelesssignals from an input device. The controllable electrical outlet may becontrolled manually (e.g., in response to remote controls) and/orautomatically (e.g., in response to sensors and/or timeclocks). Thecontrollable electrical outlet may also be configured to measure thepower consumed by electrical loads plugged into the second electricalconnection and report the power usage information via the RF signals.

In addition, a load control system for controlling one or more plug-inelectrical loads adapted to receive power from a power source isdescribed herein. The load control system may comprise a standardelectrical outlet adapted to receive power from the power source, acontrollable electrical outlet adapted to receive power from the powersource, and an input device configured to transmit a digital message tothe controllable electrical outlet. The controllable electrical outletmay comprise at least one electrical receptacle configured to receive aplug of a plug-in electrical load and an electrical connectionconfigured to be electrically coupled to the standard electrical outlet.The controllable electrical outlet may be configured to control thepower delivered to the standard electrical outlet in response to thedigital message received via the communication circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simple diagram of an example load control system having acontrollable electrical outlet.

FIG. 2 is a simplified block diagram of an example controllableelectrical outlet.

FIGS. 3A-3C are perspective views of example controllable electricaloutlets.

DETAILED DESCRIPTION

FIG. 1 is a simple diagram of an example load control system 100 havinga load control device (e.g., a controllable electrical outlet 110), aplurality of standard electrical outlets 120, and a plurality of plug-inelectrical loads (e.g., a computer 104 and a monitor 106). Thecontrollable electrical outlet 110 may be adapted to be installed in astandard electrical wallbox (not shown). The controllable electricaloutlet 110 may be adapted to be connected to a power source, such as analternating-current (AC) power source 102 for receiving a hot voltageV_(H) (e.g., an AC mains line voltage, such as 120 V at 60 Hz or 230 Vat 50 Hz) at a line voltage input 116 (e.g., a hot terminal). Thecontrollable electrical outlet 110 may also be connected to the neutralside of the AC power source 102. Alternatively or additionally, thecontrollable electrical outlet 110 may be configured to receive powerfrom a direct-current (DC) power source.

The controllable electrical outlet 110 may comprise upper and lowerreceptacles 112, 114 into which the plug of a plug-in electrical loadmay be plugged. Each receptacle 112, 114 may have a hot connection and aneutral connection for receipt of the corresponding prongs of anelectrical plug. The controllable electrical outlet 110 may provide thehot voltage V_(H) at the upper receptacle 112, such that any electricalloads plugged into the upper receptacle are continuously powered. Thecontrollable electrical outlet 110 may comprise an internal load controlcircuit (not shown), e.g., a relay for generating a switched-hot voltageV_(SH), which may be provided at the lower receptacle 114. Accordingly,any electrical loads plugged into the lower receptacle 114 may bepowered and unpowered in response to closing and opening the relay,respectively. Alternatively, the upper and lower receptacles 112, 114could both provide the hot voltage V_(H) or both could provide theswitched-hot voltage V_(SH), or the controllable electrical outlet 110may provide the hot voltage V_(H) at the lower receptacle 114 and theswitched-hot voltage V_(SH) at the upper receptacle 112.

The controllable electrical outlet 110 may also comprise a controlledwired output 118 (e.g., a switched-hot terminal) for providing theswitched voltage V_(SH) to the standard electrical outlets 120. Thestandard electrical outlets 120 may each be configured to receive boththe hot voltage V_(H) and the switched-hot voltage V_(SH). For example,the standard electrical outlets 120 may receive the hot voltage V_(H)via an electrical wire 126 connected to the line voltage input 116 ofthe controllable electrical outlet 110. The standard electrical outlets120 may receive the switched-hot voltage V_(SH) via an electrical wire128 connected to the controlled wired output 118 of the controllableelectrical outlet 110. One or more of the standard electrical outlets120 may also be connected to the neutral side of the AC power source102. The controllable electrical outlet 110 may “pass through” the hotvoltage V_(H) to provide the hot voltage V_(H) from the AC power source102 to the electrical wire 126 (e.g., directly). Alternatively, theelectrical wire 126 may be wired to the hot side of the AC power source102 around the controllable electrical outlet 110, such that the hotvoltage V_(H) does not pass through the controllable electrical outlet110 on its way to the standard electrical outlet 120.

Each of the standard electrical outlets 120 may comprise upper and lowerreceptacles 122, 124 into which an electrical load may be plugged. Theupper receptacle 122 of a standard electrical outlet 120 may beelectrically coupled to the electrical wire 126 for receiving the hotvoltage V_(H), such that any electrical loads plugged into the upperreceptacles are continuously powered. The lower receptacle 124 of astandard electrical outlet 120 may be electrically coupled to theelectrical wire 128 for receiving the switched-hot voltage V_(SH), suchthat any electrical loads plugged into the lower receptacle may bepowered and unpowered in response to the closing and opening,respectively, of the relay of the controllable electrical outlet 110.Referring to the example of FIG. 1, the computer 104 may be adapted tobe plugged into the upper receptacle 122 of one of the standardelectrical outlets 120 (e.g., such that the computer 104 is continuouslypowered), while the monitor 106 may be adapted to be plugged into thelower receptacle 124 of one of the standard electrical outlets (e.g.,such that the monitor 106 may be turned on and off by the controllableelectrical outlet 110. Alternatively, the upper and lower receptacles122, 124 of a standard electrical outlet 120 could both be coupled tothe hot voltage V_(H) or could both be coupled to the switched-hotvoltage V_(SH).

The controllable electrical outlet 110 may be configured to measure themagnitude of the total load current conducted by one or more of theplug-in electrical loads plugged into the controllable electrical outlet110 and/or the standard electrical outlets 120. For example, thecontrollable electrical outlet 110 may be configured to measure themagnitude of a first load current conducted by the switched electricalloads (e.g., the electrical loads connected to the lower receptacle124), and the magnitude of a second load current conducted by theunswitched electrical loads (e.g., the electrical loads connected to theupper receptacle 122).

The controllable electrical outlet 110 may be configured to control therelay to turn the electrical loads plugged into the lower receptacles114, 124 and/or the standard electrical outlets 120 on and off inresponse to wireless signals, e.g., radio-frequency (RF) signals 108,received from one or more input devices (e.g., RF transmitters). Forexample, the input devices may comprise a remote control device 130, anoccupancy sensor 140, and/or a system controller 150 (e.g., a centralcontroller or gateway device). As such, the controllable electricaloutlet 110 may be controlled automatically (e.g., via an occupancysensor 140) or manually (e.g., via a remote control device 130). Becausethe controllable electrical outlet 110 may comprise the controlled wiredoutput 118 for controlling the standard electrical outlets 120, thestandard electrical outlets 120 do not need to be responsive to the RFsignals 106 in order to switch the respective plug-in electrical loadson and off, thus greatly reducing the cost of the load control system100.

The remote control device 130 may comprise a battery-powered handheldremote control, or could alternatively be mounted to a wall or supportedon a pedestal to be mounted on a tabletop. Examples of battery-poweredremote control devices are described in greater detail incommonly-assigned U.S. Pat. No. 8,330,638, issued Dec. 11, 2012,entitled WIRELESS BATTERY-POWERED REMOTE CONTROL HAVING MULTIPLEMOUNTING MEANS, the entire disclosures of which are hereby incorporatedby reference.

The remote control device 130 may transmit digital messages to thecontrollable electrical outlet 110 via the RF signals 108 in response toactuations of one or more buttons 132 for turning the electrical loadsplugged into the lower receptacles 114, 124 on and off. The remotecontrol device 130 may be associated with the controllable electricaloutlet 110 by actuating one or more of the buttons 132 of the remotecontrol device and an actuator (e.g., programming button 119) of thecontrollable electrical outlet 110. Since the controllable electricaloutlet 110 may be adapted to be installed in a standard electricalwallbox and the programming button 119 may be located on thecontrollable electrical outlet 110, the programming button 119 may beeasily accessed to associate the controllable electrical outlet 110 withthe remote control device 130. In addition, the controllable electricaloutlet 110 may be installed in the same room in which the remote controldevice 130 is located to enhance the reliability of the RFcommunications. Examples of methods of associating wireless controldevices are described in greater detail in commonly-assigned U.S. PatentApplication Publication No. 2008/0111491, published May 15, 2008,entitled RADIO-FREQUENCY LIGHTING CONTROL SYSTEM; U.S. PatentApplication Publication No. 2013/0214609, published Aug. 22, 2013,entitled TWO-PART LOAD CONTROL SYSTEM MOUNTABLE TO A SINGLE ELECTRICALWALLBOX; and U.S. patent application Ser. No. 13/830,237, filed Mar. 14,2013, entitled COMMISSIONING LOAD CONTROL SYSTEMS; the entiredisclosures of which are hereby incorporated by reference.

The occupancy sensor 140 may be configured to detect occupancy andvacancy conditions in the space in which the load control system 100 isinstalled. The occupancy sensor 140 may transmit digital messages to thecontrollable electrical outlet 110 via the RF signals 108 in response todetecting the occupancy or vacancy conditions. The controllableelectrical outlet 110 may be configured to turn the electrical loadsplugged into the lower receptacles 114, 124 on in response to anoccupancy condition and off in response to a vacancy condition. Theoccupancy sensor 140 may be associated with the controllable electricaloutlet 110 by actuating a button on the occupancy sensor and/or anactuator (e.g., the programming button 119) of the controllableelectrical outlet 110. Since the controllable electrical outlet 110 maybe located in the same room as the occupancy sensor 140, the occupancysensor 140 may be easily associated with the controllable electricaloutlet 110 and reliable RF communications may be provided.Alternatively, the occupancy sensor 140 may operate as a vacancy sensorto only turn off the lighting loads in response to detecting a vacancycondition (e.g., to not turn on the lighting loads in response todetecting an occupancy condition). Examples of RF load control systemshaving occupancy and vacancy sensors are described in greater detail incommonly-assigned U.S. Pat. No. 8,009,042, issued Aug. 30, 2011 Sep. 3,2008, entitled RADIO-FREQUENCY LIGHTING CONTROL SYSTEM WITH OCCUPANCYSENSING; U.S. Pat. No. 8,199,010, issued Jun. 12, 2012, entitled METHODAND APPARATUS FOR CONFIGURING A WIRELESS SENSOR; and U.S. Pat. No.8,228,184, issued Jul. 24, 2012, entitled BATTERY-POWERED OCCUPANCYSENSOR, the entire disclosures of which are hereby incorporated byreference.

The system controller 150 may be configured to communicate with anetwork 152 (e.g., a wireless or wired local area network) via a wireddigital communication link 154 (e.g., an Ethernet communication link)for access to the Internet. Alternatively or additionally, the systemcontroller 150 may be wirelessly connected to the network 152, e.g.,using Long-Term Evolution (LTE) or Wi-Fi technology. For example, thesystem controller 150 may be configured to receive digital messages(e.g., Internet Protocol packets) via the network 152 from a networkdevice (not shown), such as a smart phone (e.g., an iPhone® smart phone,an Android® smart phone, or a Blackberry® smart phone), a personalcomputer, a laptop, a wireless-capable media device (e.g., MP3 player,gaming device, or television), a tablet device, (e.g., an iPad®hand-held computing device), a Wi-Fi or wireless-communication-capabletelevision, or any other suitable Internet-Protocol-enabled device.Examples of load control systems operable to communicate with networkdevices on a network are described in greater detail incommonly-assigned U.S. Patent Application Publication No. 2013/0030589,published Jan. 31, 2013, entitled LOAD CONTROL DEVICE HAVING INTERNETCONNECTIVITY, the entire disclosure of which is hereby incorporated byreference.

The system controller 150 may operate as a central controller for theload control system 100. The system controller 150 may operate as agateway device to simply relay digital messages between the network 152and the controllable electrical outlet 110. The system controller 150may be configured to transmit digital messages via the RF signals 108 tothe controllable electrical outlet 110 for turning on and off theelectrical loads plugged into the controllable electrical outlet 110and/or the standard electrical outlets 120. Accordingly, thecontrollable electrical outlet 110 may be responsive to data received bythe system controller 150 from the Internet, such as weather informationand emergency status information. The system controller 150 may befurther configured to transmit digital messages including one or moreof: a timeclock command, a load shed command, a demand response command,a peak demand command, or time-of-day pricing information. The systemcontroller 150 may be configured to control the controllable electricaloutlet 110 in accordance with one or more timeclock events of atimeclock schedule, for example, to turn on the switched electricalloads during the day and to turn off the switched electrical loads atnight. In addition, the controllable electrical outlet 110 may beconfigured to transmit feedback information, such as the status andenergy consumption of the controlled loads (e.g., load current), back tothe system controller 150, which may be configured to report theinformation to an external device via the network 152.

The controllable electrical outlet 110 may be configured to storeinformation regarding the type of input device from which thecontrollable electrical outlet 100 received the digital message. Thecontrollable electrical outlet 110 may be configured to storeinformation regarding how the controllable electrical outlet 110controlled the electrical loads in response to receiving the digitalmessage. For example, this may be performed by the controller electricaloutlet 110 after controlling the electrical loads plugged into thecontrollable electrical outlet 110 and/or the standard electricaloutlets 120 in response to a digital messages received via the RFsignals 108. The controllable electrical outlet 110 may transmit thisinformation to the system controller 150. The system controller 150 mayanalyze this information to determine how much energy is saved inresponse to certain types of input devices. For example, the systemcontroller 150 may be configured to determine how much energy is savedas a result of the controllable electrical outlet 110 turning off theelectrical loads plugged into the controllable electrical outlet 110and/or the standard electrical outlets 120 in response to the occupancysensor 140 versus how much energy is saved as a result of thecontrollable electrical outlet turning off the electrical loads inresponse to the remote control device 130.

The controllable electrical outlet 110 may be configured to determine abalance between the amount of power consumed by the switched andunswitched electrical loads and report this information to the systemcontroller 150. The system controller 150 may be configured to transmit(e.g., to a network device via the network 152) a digital messageincluding an alert that the amount of power consumed by the switched andunswitched electrical loads is unbalanced, for example, if theunswitched electrical loads are consuming a much greater amount of powerthan the switched electrical loads. For example, the alert may beincluded in an email or text message sent to a building manager.

Some plug-in electrical loads may still consume energy to maintain astandby mode when off. These electrical loads may be referred to as“vampire” loads. In addition, some plug-in power supplies may stillconsume energy even when the power supply is not charging a rechargeableload. The controllable electrical outlet 110 may be configured to detectwhether one or more of the plug-in electrical loads plugged into thecontrollable electrical outlet 110 and/or the standard electricaloutlets 120 are off, are in the standby mode, and/or are not charging arechargeable load. The controllable electrical outlet 110 may beconfigured to determine that a plug-in electrical load is off, is instandby mode, and/or is not charging a rechargeable load if themagnitude of the load current conducted by the plug-in electrical loadis less than a predetermined current threshold. For example, thecontrollable electrical outlet 110 may be configured to remove powerfrom the plug-in electrical load if the controllable electrical outlethas received a digital message indicating a vacancy condition from theoccupancy sensor 140 and has determined that the plug-in electrical loadis off, is in the standby mode, and/or is not charging a rechargeableload. The controllable electrical outlet 110 will not remove power fromthe plug-in electrical load when the load is on or charging. Forexample, if a television is on, the television is considered to be inuse independent of whether the room is occupied or not. Perhaps the useris listening to a particular program on the television from anotherroom. When the television is turned off (e.g., changed to standby mode),the controllable electrical outlet 110 may disconnect the televisionfrom the AC power source when the room becomes unoccupied, for example,to save energy.

The plug-in electrical load may be configured to communicate (e.g.,wirelessly communicate), to the system controller 150, informationrelating to whether the plug-in electrical load is off, in the standbymode, and/or not charging a rechargeable load. For example, the plug-inelectrical load may be configured to send a digital message to thesystem controller 150 when the plug-in electrical load is in the standbymode. Accordingly, the system controller 150 may be configured todetermine that the plug-in electrical load is in a standby mode andcontrol the controllable electrical outlet 110 (e.g., the load controlcircuit of the controllable electrical outlet 110) to disconnect powerfrom the plug-in electrical load. For example, the system controller 150may send a digital message to the controllable electrical outlet 110indicating that the controllable electrical outlet 110 should disconnectpower from the plug-in electrical load.

The plug-in electrical load may be configured to communicate (e.g.,wirelessly communicate), to the system controller 150, informationrelating to an electrical signature of the plug-in electrical load. Thesystem controller 150 may be configured to compare the electricalsignature of the plug-in electrical load to one or more electricalsignatures stored in a memory. The system controller 150 may beconfigured to send a digital message to the controllable electricaloutlet 110 to cease controlling the power delivered to the plug-inelectrical load in response to the digital message, for example, if theelectrical signature of the plug-in electrical load matches one of theelectrical signatures stored in the memory.

Some plug-in electrical loads may be critical loads that should becontinuously powered (e.g., computers, medical devices, etc.). Thecontrollable electrical outlet 110 may be configured to determine if acritical load is plugged into the controllable electrical outlet 110and/or the standard electrical outlets 120 and to prevent the criticalload from being turned off, e.g., by disabling control of the criticalload by the input devices (e.g., the remote control device 130, theoccupancy sensor 140, and/or the controller 150). For example, thecontrollable electrical outlet 110 may be configured to determine thatthe computer 104 is plugged into one of the controllable electricaloutlet 110 and/or the standard electrical outlets 120 by monitoring anelectrical signature of the load current drawn by the computer. Thecontrollable electrical outlet 110 may be configured to record and storethe electrical signature of the load current conducted by the computer104 when the computer 104 is plugged into the controllable electricaloutlet 110 and/or the standard electrical outlets 120, e.g., when theload control system 100 is first configured after installation. Thecontrollable electrical outlet 110 may also have one or morepredetermined electrical signatures of critical loads stored in memoryprior to installation. During normal operation, the controllableelectrical outlet 110 may be configured to compare an electricalsignature drawn by an electrical load to one or more of the plurality ofelectrical signatures stored in memory. If the controllable electricaloutlet 110 determines that an electrical load plugged into thecontrollable electrical outlet 110 and/or a standard electrical outlet120 is a critical load via its electrical signature (e.g., that theelectrical load is the computer 104), the controllable electrical outlet110 may be configured to continuously power the electrical load at alltimes, e.g., by not disconnecting power from the electrical load inresponse to the remote control device 130, the occupancy sensor 140,and/or the controller 150.

The controllable electrical outlet 110 may be configured to determinethat the room in which an electrical load (e.g., the computer 104 and/orthe monitor 106) is located is occupied in response to the magnitudes ofthe load currents conducted by the switched and/or unswitched electricalloads. For example, if the magnitude of the load current conducted bythe computer 104 has increased and/or is actively changing, thecontrollable electrical outlet 110 may be configured to determine thatthe room in occupied. If the controllable electrical outlet 110determines that one or more of the electrical loads plugged into thecontrollable electrical outlet 110 and/or the standard electricaloutlets 120 are off, are in the standby mode, and/or are not charging arechargeable load, the controllable electrical outlet 110 may determinethat the room is vacant. The controllable electrical outlet 110 may beconfigured to turn on and off the electrical loads plugged into thecontrollable electrical outlet 110 and/or the standard electricaloutlets 120 in response to the occupancy and/or vacancy conditionsdetermined from the magnitudes of the load currents. Alternatively oradditionally, the system controller 150 may be configured to determineinformation regarding an occupancy or vacancy condition in a space inwhich the controllable electrical outlet 110 is installed in response tothe magnitude of the load current measured by the controllableelectrical outlet 110. For example, the controllable electrical outlet110 may transmit, to the system controller 150, a digital message thatincludes information relating to the magnitudes of the load currentsconducted by the switched and/or unswitched electrical loads.

As described above, the remote control device 130, the occupancy sensor140, and/or the system controller 150 may operate as a control-sourcedevice (e.g., an RF transmitter) and the controllable electrical outlet110 may operate as a control-target device (e.g., an RF receiver).Alternatively or additionally, the control devices of the load controlsystem 100 may comprise an RF transceiver, such that the devices areable to transmit and receive the RF signals 108. For example, thecontrollable electrical outlet 110 may be configured to transmitfeedback information, such as the status and energy consumption of thecontrolled loads, back to the system controller 150, which may beconfigured to report the information to external devices via the network152. Examples of RF load control systems are described incommonly-assigned U.S. Pat. No. 5,905,442, issued on May 18, 1999,entitled METHOD AND APPARATUS FOR CONTROLLING AND DETERMINING THE STATUSOF ELECTRICAL DEVICES FROM REMOTE LOCATIONS, and U.S. Patent ApplicationPublication No. 2014/0001977, published Jan. 2, 2014, entitled LOADCONTROL SYSTEM HAVING INDEPENDENTLY-CONTROLLED UNITS RESPONSIVE TO ABROADCAST CONTROLLER, the entire disclosures of which are both herebyincorporated by reference.

In addition, the controllable electrical outlet 110 may operate a signalrepeater of the load control system 100. For example, the controllableelectrical outlet 110 may be configured to receive a digital messagefrom one of the control devices of the load control system 100 (e.g.,the remote control device 130, the occupancy sensor 140, the systemcontroller 150, or another controllable electrical outlet) and toretransmit the digital message to other control devices of the loadcontrol system (e.g., the system controller 150 or another controllableelectrical outlet). Examples of RF load control systems having signalrepeaters are described in greater detail in commonly-assigned U.S. Pat.No. 5,848,054, issued Dec. 8, 1998, entitled REPEATER FOR TRANSMISSIONSYSTEM FOR CONTROLLING AND DETERMINING THE STATUS OF ELECTRICAL DEVICESFROM REMOTE LOCATIONS, and U.S. Pat. No. 6,803,728, issued Oct. 12,2004, entitled SYSTEM FOR CONTROL OF DEVICES, the entire disclosures ofwhich are hereby incorporated by reference.

Since the controllable electrical outlet 110 may be adapted to beinstalled in the standard electrical wallbox and may be responsive tothe RF signals 108 (e.g., that are transmitted directly to thecontrollable electrical outlet 110), the load control system 100 may notrequire any additional control devices (e.g., load control devicesinstalled above the ceiling of the room, behind the walls of the room,or in an electrical closet) in order to provide control of theelectrical loads plugged into the controllable electrical outlet 110 andthe standard electrical outlets 120 in response to the RF signals 108.This reduces the overall cost of the load control system 100 andsimplifies the installation of the load control system 100 since noadditional control devices need to be installed.

The controllable electrical outlet 110 could be responsive to othertypes of input devices, such as, for example, daylight sensors,radiometers, cloudy-day sensors, shadow sensors, window sensors,temperature sensors, humidity sensors, pressure sensors, smokedetectors, carbon monoxide detectors, air-quality sensors, motionsensors, security sensors, proximity sensors, fixture sensors, partitionsensors, keypads, kinetic or solar-powered remote controls, key fobs,cell phones, smart phones, tablets, personal digital assistants,personal computers, laptops, timeclocks, audio-visual controls, safetydevices (such as fire protection, water protection, and medicalemergency devices), power monitoring devices (such as power meters,energy meters, utility submeters, utility rate meters), residential,commercial, or industrial controllers, interface devices with othercontrol systems (such as security systems and emergency alert systems),and/or any combination of these input devices. One or more of thedifferent types of input devices may be provided in a single loadcontrol system 100.

The load control system 100 may also comprise one or more other types ofplug-in electrical load and/or switched electrical loads, such as, forexample, lighting loads (e.g., incandescent lamps, halogen lamps,electronic low-voltage lighting loads, and magnetic low-voltage lightingloads); dimming ballasts for driving gas-discharge lamps; light-emittingdiode (LED) drivers for driving LED light sources; table or floor lamps;screw-in luminaires including dimmer circuits and incandescent orhalogen lamps; screw-in luminaires including ballasts and compactfluorescent lamps; screw-in luminaires including LED drivers and LEDlight sources; motor loads, such as ceiling fans and exhaust fans;motorized window treatments; projection screens; motorized interior orexterior shutters; heating and/or cooling systems; heating, ventilation,and air-conditioning (HVAC) systems; air conditioners; compressors;electric baseboard heater controllers; controllable dampers; variableair volume controllers; fresh air intake controllers; ventilationcontrollers; hydraulic valves for use in radiators and radiant heatingsystem; humidity control units; humidifiers; dehumidifiers; waterheaters; boiler controllers; pool pumps; refrigerators; freezers;appliances; televisions; computer monitors; printers; copiers; faxmachines; video cameras; audio systems; amplifiers; speakers; overheadprojectors; visual presenters; smart boards; coffee makers; toasters;elevators; power supplies; generators; electric chargers; electricvehicle chargers; medical devices (e.g., heart/lung machines), oralternative energy controllers.

FIG. 2 is a simplified block diagram of an example controllableelectrical outlet 200 that may be deployed as, for example, thecontrollable electrical outlet 110 of the load control system 100 shownin FIG. 1. The controllable electrical outlet 200 may be adapted to bemounted in a standard electrical wallbox. As shown, the controllableelectrical outlet 200 may include a line-side hot electrical connectionH_(LINE) (e.g., the line voltage input 116) and a line-side neutralelectrical connection N_(LINE). The line-side hot electrical connectionH_(LINE) and the line-side neutral electrical connection N_(LINE) may becoupled to an AC power source 202 (e.g., the AC power source 102) forreceiving a power source voltage (e.g., the hot voltage V_(H)) from theAC power source 202. The controllable electrical outlet 200 may furthercomprise a first load-side hot electrical connection H_(LOAD1) and afirst load-side neutral electrical connection N_(OUT1), which may beprovided at an electrical receptacle (e.g., the upper unswitchedreceptacle 112 of the controllable electrical outlet 110) for powering afirst electrical load (e.g., a first plug-in electrical load). The hotvoltage V_(H) received at the line-side hot electrical connectionH_(LINE) may be fed through the controllable electrical outlet 200 tothe first load-side hot electrical connection H_(LOAD1).

The controllable electrical outlet 200 may further comprise a secondload-side hot electrical connection H_(LOAD2) and a second load-sideneutral electrical connection N_(LOAD2), which may also be provided atan electrical receptacle (e.g., the lower switched receptacle 114 of thecontrollable electrical outlet 110) for powering a second electricalload (e.g., a second plug-in electrical load). The controllableelectrical outlet 200 may comprise a load control circuit 210 (e.g., acontrollable switching circuit, such as a relay) coupled in serieselectrical connection between the line-side hot electrical connectionH_(LINE) and the second load-side hot electrical connection H_(LOAD2).The load control circuit 210 may comprise a relay having a single-polesingle-throw (SPST) mechanical switch coupled in series electricalconnection between the line-side hot electrical connection H_(LINE) andthe second load-side hot electrical connection H_(LOAD2) and at leastone operating coil for opening and closing the SPST switch. The loadcontrol circuit 210 may be rendered conductive and non-conductive inresponse to a control circuit 212 (e.g., a digital control circuit) toprovide a switched-hot voltage (e.g., the switched-hot voltage V_(SH))at the second load-side hot electrical connection H_(LOAD2) for turningthe second electrical load on and off. For example, the control circuit212 may be coupled to the at least one operating coil of the relay foropening and closing the SPST switch of the relay. The control circuit212 may include one or more of a processor (e.g., a microprocessor), amicrocontroller, a programmable logic device (PLD), a field programmablegate array (FPGA), an application specific integrated circuit (ASIC), orany suitable processing device.

The controllable electrical outlet 200 may further comprises a thirdload-side hot electrical connection H_(LOAD3) and a third load-sideneutral electrical connection N_(LOAD3). For example, the thirdload-side hot electrical connection H_(LOAD3) may be provided at a wiredelectrical connection, such as a screw terminal (e.g., the controlledwired output 118 of the controllable electrical outlet 110) for poweringone or more downstream standard electrical outlets (e.g., the standardelectrical outlets 120). The third load-side neutral electricalconnection N_(LOAD3) may also be provided at a screw terminal. However,the third load-side neutral electrical connection N_(LOAD3) may be anoptional connection since the third load-side neutral electricalconnection N_(LOAD3) is coupled to the line-side neutral electricalconnection N_(LINE) (e.g., which is coupled to the neutral side of theAC power source 202). The switched-hot voltage V_(SH) may be provided atthe third load-side switched-hot electrical connection H_(LOAD3). Thedownstream electrical outlets may receive the switched-hot voltageV_(SH) via an electrical wire 208 (e.g., the electrical wire 128 of FIG.1). The control circuit 212 may be configured to control the loadcontrol circuit 210 for connecting power to or disconnecting power fromone or more of the receptacles of each of the downstream electricaloutlets. The downstream electrical outlets may receive the hot voltageV_(H) via an electrical wire (e.g., the electrical wire 126 of FIG. 1)that is wired to the line-side hot electrical connection H_(LINE) in theelectrical wallbox of the controllable electrical outlet 200.

Alternatively or additionally, the load control circuit 210 may comprisea dimmer circuit or driver circuit for controlling the amount of powerdelivered to the electrical loads connected to the second load-side hotelectrical connection H_(LOAD2), the third load-side hot electricalconnection H_(LOAD3), and/or the downstream electrical outlets. Forexample, the load control circuit 210 may comprise a bidirectionalsemiconductor switch (e.g., a triac), which may be controlled by thecontrol circuit 212 using a standard phase-control dimming technique.

The controllable electrical outlet 200 may comprise one or more sensecircuits for detecting and/or measuring the power being consumed by theelectrical loads plugged into the controllable electrical outlet 200and/or the downstream electrical outlets. For example, the controllableelectrical outlet 200 may comprise a first sense circuit 214 coupled inseries between the line-side hot electrical connection H_(LINE) and thefirst load-side hot electrical connection H_(LOAD1) for measuring a loadcurrent conducted by the first electrical load, and a second sensecircuit 216 coupled in series with the load control circuit 210 formeasuring a load current conducted by the second electrical loads andone or more electrical loads plugged into the downstream electricaloutlets. The sense circuits 214, 216 may generate respective first andsecond sense signals V_(S1), V_(S2) that are received by the controlcircuit 212 and are representative of the magnitudes of the respectiveload currents.

While the downstream electrical outlets may receive the hot voltageV_(H) via an electrical wire that is wired to the line-side hotelectrical connection H_(LINE) as described above, the downstreamelectrical outlets could (e.g., alternatively) receive power through thecontrollable electrical outlet 200. For example, the controllableelectrical outlet 200 could comprise one or more additional electricalconnections to which the unswitched receptacles of the downstreamelectrical outlets could be connected. The first sense circuit 214 couldbe coupled to the additional electrical connections, for example, suchthat a total load current of the first electrical load and theunswitched receptacles of the downstream electrical outlets may beconducted through the first sense circuit 214. Accordingly, themagnitude of the first sense signal V_(S1) generated by the first sensecircuit 214 may be representative of the total load current of theunswitched electrical loads coupled to the controllable electricaloutlet 200, and the magnitude of the second sense signal V_(S2)generated by the sense circuit 216 may be representative of the totalload current of the switched electrical loads controlled by thecontrollable electrical outlet 200.

The controllable electrical outlet 200 may comprise a communicationcircuit 218, for example, a wireless communication circuit (e.g., an RFtransceiver coupled to an antenna) for transmitting and receivingdigital messages (e.g., via wireless signals, such as the RF signals 108of FIG. 1). The communication circuit 218 may be configured to receivethe digital messages via the RF signals 108 according to a predefined RFcommunication protocol, such as, for example, one or more of LUTRONCLEAR CONNECT, WIFI, BLUETOOTH, ZIGBEE, Z-WAVE, KNX-RF, LTE, or ENOCEANRADIO protocols. Alternatively, the communication circuit 218 maycomprise an RF transmitter for only transmitting RF signals and/or an RFreceiver for only receiving RF signals. The controllable electricaloutlet 200 may be configured to receive the digital messages via adifferent wireless medium, such as, for example, infrared (IR) signalsor sound (e.g., voice). In addition, the communication circuit 218 maycomprise a power-line communication (PLC) circuit and/or a wiredcommunication circuit, for example, a digital communication linkoperating in accordance with a predefined communication protocol (e.g.,of Ethernet, IP, XML, Web Services, QS, DMX, BACnet, Modbus, LonWorks,and/or KNX protocols), a serial digital communication link, an RS-485communication link, an RS-232 communication link, a digital addressablelighting interface (DALI) communication link, a LUTRON ECOSYSTEMcommunication link, or an analog control link. In addition, thecommunication circuit 218 could be adapted to receive one of aline-voltage control signal, a phase-control signal, a 0-10V controlsignal, and a contact closure output control signal.

The controllable electrical outlet 200 may comprise a memory 220communicatively coupled to the control circuit 212. The control circuit212 may be configured to use the memory 220 for the storage and/orretrieval of, for example, the serial numbers of the input devices(e.g., the wireless transmitters) to which the controllable electricaloutlet 200 is responsive (e.g., associated with). The memory 220 may beimplemented as an external integrated circuit (IC) or as an internalcircuit of the control circuit 212.

The controllable electrical outlet 200 may comprise one or moreactuators 222 (e.g., buttons) for providing manual user inputs to thecontrol circuit 212. For example, the control circuit 212 may beconfigured to control the load control circuit 210 to render the relayconductive and non-conductive in response to actuations of the actuators222. In addition, the control circuit 212 may be configured to associatethe controllable electrical outlet 200 with one or more of the inputdevices (e.g., the remote control device 130, the occupancy sensor 140,and the controller 150) in response to actuations of one or more of theactuators 222 (e.g., the programming button 119 of the controllableelectrical outlet 110).

The controllable electrical outlet 200 may include a power supply 224coupled between the line-side hot electrical connection H_(LINE) and theline-side neutral electrical connection N_(LINE) for generating a DCsupply voltage V_(CC) for powering one or more of the control circuit212, the communication circuit 218, the memory 220, and otherlow-voltage circuitry of the controllable electrical outlet 200.

The control circuit 212 may be configured to control the load controlcircuit 210 to render the relay conductive and non-conductive inresponse to digital messages received via RF signals from input devices(e.g., the remote control device 130, the occupancy sensor 140, and thesystem controller 150 shown in FIG. 1). For example, the control circuit212 may receive digital messages including commands for providing manualcontrol of the switched electrical loads (e.g., from the remote controldevice 130) and/or for providing automated control of the switchedelectrical loads (e.g., from the occupancy sensor 140 and/or the systemcontroller 150). A system controller (e.g., the system controller 150)may be configured to transmit digital messages to the controllableelectrical outlet 200 to control the switched electrical loads inaccordance with one or more timeclock events of a timeclock schedule,for example, to turn on the switched electrical loads during the day andto turn off the switched electrical loads at night. In addition, thecontrol circuit 212 may be configured to cause the communication circuit218 to transmit, for example, one or more digital messages includinginformation regarding the power consumed by the unswitched and/orswitched electrical loads to the system controller.

After controlling the load control circuit 210 in response to digitalmessages received via the communication circuit 218, the control circuit212 may be configured to store in the memory 220 information regardingthe type of input device from which the communication circuit 218received the digital message, and/or how the control circuit 212controlled the load control circuit 210 in response to that digitalmessage. The control circuit 212 may transmit this information to thesystem controller for analysis regarding how much energy is saved inresponse to certain types of input devices. For example, the systemcontroller 150 may be configured to determine how much energy is savedas a result of the controllable electrical outlet 200 turning off thecontrolled electrical loads in response to the occupancy sensor 140versus how much energy is saved as a result of the controllableelectrical outlet turning off the controlled electrical loads inresponse to the remote control device 130.

The control circuit 210 may be configured to measure the amount of powerconsumed by the unswitched electrical loads (e.g., in response to thefirst sense signal V_(S1) generated by the first sense circuit 214)and/or to determine the amount of power consumed by the switchedelectrical loads (e.g., in response to the second sense signal V_(S2)generated by the sense circuit 216). The control circuit 210 may beconfigured to determine a balance between the amount of power consumedby the unswitched and switched electrical loads and report thisinformation to the system controller. The controllable electrical outlet200 and/or the system controller may be configured to transmit a digitalmessage including an alert that the amount of power consumed by theunswitched and switched electrical loads is unbalanced (e.g., in anemail or text message).

The control circuit 212 may be configured to detect whether one or moreof the electrical loads plugged into the controllable electrical outletand/or the downstream electrical outlets are off, are in the standbymode, and/or are not charging a rechargeable load. The control circuit212 may be configured to determine that a plug-in electrical load isoff, is in standby mode, and/or is not charging a rechargeable load ifthe magnitude of the load current conducted by the plug-in electricalload is less than a predetermined current threshold. For example, thecontrol circuit 212 may be configured to control the load controlcircuit 210 to remove power from the plug-in electrical load if thecontrol circuit has received a digital message indicating a vacancycondition from an occupancy or vacancy sensor and has determined thatthe plug-in electrical load is off, is in the standby mode, and/or isnot charging a rechargeable load. The control circuit 212 may not removepower from the plug-in electrical load when the load is on or charging.

The control circuit 212 may be configured to determine if a criticalload is plugged into the controllable electrical outlet 220 and/or thedownstream electrical outlets. The control circuit 212 may be configuredto disable control of the critical load by the input devices (e.g., theremote control device 130, the occupancy sensor 140, and/or thecontroller 150). For example, the control circuit 212 may be configuredto determine that a particular plug-in electrical load (e.g., acomputer) is plugged into one of the controllable electrical outletand/or the downstream electrical outlets by monitoring an electricalsignature of the load current drawn by the electrical load. The controlcircuit 212 may be configured to record the electrical signature of theload current conducted by a plug-in electrical load plugged into thecontrollable electrical outlet 200 and/or the downstream electricaloutlets (e.g., using one of the first and second sense circuits 214,216) and to store the recorded electrical signature in the memory 220.The controllable electrical outlet 200 may have one or morepredetermined electrical signatures of critical loads stored in thememory 220 prior to installation. The control circuit 212 may beconfigured to compare an electrical signature drawn by a plug-inelectrical load plugged into the controllable electrical outlet 200and/or the downstream electrical outlets to one or more of the pluralityof electrical signatures stored in the memory 220. If the electricalsignature shows that the electrical load plugged into one of thecontrollable electrical outlet 200 and/or the downstream electricaloutlets is a critical load, the control circuit 212 may be configured tocontinuously power the critical load at all times. For example, thecontrollable electrical outlet 200 may prevent power from beingdisconnected from the critical load in response to a signal receivedfrom an input device (e.g., the remote control device 130, the occupancysensor 140, and/or the controller 150).

The control circuit 212 may be configured to determine that the room inwhich the controllable electrical outlet 200 is located is occupiedbased on a magnitude of the load current conducted by an electrical loadplugged into the controllable electrical outlet 200 and/or a downstreamelectrical outlet. For example, if the magnitude of the load currentconducted by a particular plug-in electrical load has increased and/oris actively changing, the control circuit 212 may be configured todetermine that the room in occupied. If the control circuit 212determines that one or more of the electrical loads plugged into thecontrollable electrical outlet 200 and/or the downstream electricaloutlets are off, are in the standby mode, and/or are not charging arechargeable load, the control circuit 212 may determine that the roomis vacant. The control circuit 212 may be configured to control the loadcontrol circuit 210 in response to the occupancy and/or vacancyconditions determined from the magnitudes of one or more load currents.

FIG. 3A is a perspective view of an example controllable electricaloutlet 300. The controllable electrical outlet 300 may be an example ofthe controllable electrical outlet 110 of FIG. 1 and/or the controllableelectrical outlet 200 of FIG. 2. The controllable electrical outlet 300may comprise a front enclosure portion 302 and a rear enclosure portion304. The controllable electrical outlet 300 may be mounted to a standardelectrical wallbox. The controllable electrical outlet 300 may includesimilar circuitry as the controllable electrical outlet 200 (as shownFIG. 2), which may be housed in both the front and rear enclosureportions 302, 304. For example, a portion of the electrical circuitrymay be located in the rear enclosure portion 304 (e.g., the load controlcircuit 210 and the power supply 224) and a portion of the electricalcircuitry may be located in the front enclosure portion 302 (e.g., thecontrol circuit 212, the memory 220, and the wireless communicationcircuit 218). Accordingly, the controllable electrical outlet 300 maycomprise a wireless communication circuit that is located outside of theelectrical wallbox. The front enclosure portion 302 may comprise aprogramming button 306 (e.g., the programming button 119 and/or one ofthe actuators 222), which may be actuated to associate the controllableelectrical outlet 300 with one or more input devices (e.g., wirelesstransmitters). The controllable electrical outlet 300 may be responsiveto RF signals and may be installed in the same room in which the inputdevices are located to enhance the reliability of the RF communications.

The rear enclosure portion 304 may comprise a hot screw terminal 308 forreceiving a hot voltage from an AC power source (e.g., the line voltageinput 116 of the controllable electrical outlet 110 and/or the line-sidehot electrical connection H_(LINE) of the controllable electrical outlet200). The rear enclosure portion 304 may also comprise at least oneneutral terminal (not shown) adapted to be coupled to the neutral sideof the AC power source (e.g., the line-side neutral electricalconnection N_(LINE) of the controllable electrical outlet 200). The rearenclosure portion 304 may comprise a wired-output screw terminal 310(e.g., the controlled wired output 118 of the controllable electricaloutlet 110 and/or the third load-side hot electrical connectionH_(LOAD3) of the controllable electrical outlet 200). The wired-outputscrew terminal 310 may be adapted to be electrically connected to one ormore downstream standard electrical outlets (e.g., the standardelectrical outlets 120). The controllable electrical outlet 300 mayprovide a switched-hot voltage V_(SH) at the wired-output screw terminal310, such that the controllable electrical outlet may be able to connectpower to or disconnect power from one or more of the receptacles of eachof the downstream electrical outlets.

The front enclosure portion 302 may comprise upper and lower receptacles312, 314 for receiving the plugs of plug-in electrical loads. Forexample, the upper receptacle 312 may be an unswitched receptacle (e.g.,similar to the upper receptacle 112 of the controllable electricaloutlet 110 and/or the first load-side hot and neutral electricalconnections H_(LOAD1), N_(LOAD1) of the controllable electrical outlet200) and the lower receptacle 314 may be a switched receptacle (e.g.,similar to the lower receptacle 114 of the controllable electricaloutlet 110 and/or the second load-side hot and neutral electricalconnections H_(LOAD2,) N_(LOAD2) of the controllable electrical outlet200). The controllable electrical outlet 300 may also comprisereceptacles located on the sides, top, and/or bottom of the frontenclosure portion 302 (not shown).

The front enclosure portion 302 may be configured to be detached fromthe rear enclosure portion 304. The controllable electrical outlet 300may comprise a mounting yoke (not shown) that may be connected to therear enclosure portion 304. The mounting yoke may be mounted to theelectrical wallbox while the front enclosure portion 302 is detachedfrom the rear enclosure portion 304. The hot screw terminal 308 may beconnected to the AC power source and the wired-output screw terminal 310may be connected to the downstream electrical outlets. After the rearenclosure portion 304 is mounted to the wallbox, the front enclosureportion 302 may be attached to the rear enclosure portion 304, e.g., viaa mounting screw 316. The front enclosure portion 302 may be adapted tobe located (e.g., mostly located) outside the electrical wallbox.

FIG. 3B is a perspective view of another example controllable electricaloutlet 320. The controllable electrical outlet 320 may be an example ofthe controllable electrical outlet 110 of FIG. 1 and/or the controllableelectrical outlet 200 of FIG. 2. The controllable electrical outlet 320may be mounted to an electrical wallbox. The controllable electricaloutlet 320 may comprise a bezel portion 322 adapted to be receivedthrough an opening of a faceplate 325. The controllable electricaloutlet 320 may include circuitry that is similar to the circuitry of thecontrollable electrical outlet 200. The circuitry may be housed (e.g.,housed entirely) in a rear enclosure portion 324 of the controllableelectrical outlet 320, for example, such that a wireless communicationcircuit (e.g., the wireless communication circuit 218) may be locatedinside of the wallbox. An actuator, such as a programming button 326 maybe provided on the bezel portion 322. The programming button 326 may beactuated to associate the controllable electrical outlet 320 with one ormore input devices (e.g., wireless transmitters).

The bezel portion 322 may comprise an upper receptacle 332 (e.g., anunswitched receptacle) and a lower receptacle 334 (e.g., a switchedreceptacle) for receiving the plugs of plug-in electrical loads (e.g.,such as on the controllable electrical outlet 300 shown in FIG. 3A). Thecontrollable electrical outlet 320 may comprise a mounting yoke (notshown) that is connected to the rear enclosure portion 324 and allowsthe controllable electrical outlet 320 to be mounted to the electricalwallbox. The faceplate 325 may be attached to the mounting yoke via oneor more screws, such as the two screws 336 shown in the example of FIG.3B. The controllable electrical outlet 320 may be responsive to RFsignals and may be installed in the same room in which the input devicesare located to enhance the reliability of the RF communications.

The rear enclosure portion 324 may comprise a hot screw terminal 328 forreceiving a hot voltage from an AC power source and a neutral terminal(not shown) adapted to be coupled to the neutral side of the AC powersource (e.g., similar to the controllable electrical outlet 300 shown inFIG. 3A). The rear enclosure portion 324 may also comprise awired-output screw terminal 330 adapted to be electrically connected toone or more downstream standard electrical outlets. The controllableelectrical outlet 320 may provide a switched-hot voltage at thewired-output screw terminal 330, such that the controllable electricaloutlet 320 is able to connect power to or disconnect power from one ormore of the receptacles of one or more downstream electrical outlets.

FIG. 3C is a perspective view of another example controllable electricaloutlet 350. The controllable electrical outlet 350 may be an example ofthe controllable electrical outlet 110 of FIG. 1 and/or the controllableelectrical outlet 200 of FIG. 2. The controllable electrical outlet 350may be configured to be plugged into a standard electrical outlet 340that has upper and lower receptacles 342, 344. The standard electricaloutlet 340 may comprise a rear enclosure 345 having a first hot screwterminal 346 for receiving a hot voltage from an AC power source, asecond hot screw terminal 348 adapted to be electrically connected toone or more downstream standard electrical outlets, and at least oneneutral terminal (not shown) adapted to be coupled to the neutral sideof the AC power. The first hot screw terminal 346 may be electricallyconnected to the upper receptacle 342 and the second hot screw terminal348 may be electrically connected to the lower receptacle 344. Thestandard electrical outlet 340 may be adapted to be mounted to astandard electrical wallbox.

The controllable electrical outlet 350 may comprise an enclosure 352having upper and lower electrical receptacles 354, 356 (for receivingthe plugs of plug-in electrical loads) provided on a front surface 358.The controllable electrical outlet 350 may comprise upper and lowerelectrical plugs 360, 362 provided on a rear surface 364. The upper andlower electrical plugs 360, 362 may be adapted to plug into the upperand lower receptacles 342, 344 of the standard electrical outlet 340,respectively. Accordingly, the upper electrical plug 360 may be adaptedto be coupled to the AC power source via the upper receptacle 342 forreceiving the hot voltage V_(H). As such, the upper electrical plug 360may receive the hot voltage V_(H), which for example, may be similar toas described with reference to the line-side hot and neutral electricalconnections H_(LINE), N_(LINE) of the controllable electrical outlet200. The lower electrical plug 362 may be adapted to be coupled to thedownstream electrical outlets via the lower receptacle 344. As such, thelower electrical plug 362 may operate similar to the third load-side hotand neutral electrical connections H_(LOAD3), N_(LOAD3) of thecontrollable electrical outlet 200. Thus, the upper electrical plug 360may operate similar to the line voltage input 116 of FIG. 1, while thelower electrical plug 362 may operate similar to the wired output 118 ofFIG. 1.

The controllable electrical outlet 350 may include circuitry that issimilar to the circuitry of the controllable electrical outlet 200. Thecircuitry may be housed (e.g., housed entirely) in the enclosure 352 ofthe controllable electrical outlet 350 (e.g., such that the wirelesscommunication circuit 218 may be located outside of the wallbox). Forexample, the upper receptacle 354 may be an unswitched receptacle andthe lower receptacle 356 may be a switched receptacle. The enclosure 352may comprise a programming button 366 (e.g., the programming button 119and/or one of the actuators 222), which may be actuated to associate thecontrollable electrical outlet 350 with one or more input devices (e.g.,wireless transmitters). The controllable electrical outlet 350 may beresponsive to RF signals and may be installed in the same room in whichthe input devices are located to enhance the reliability of the RFcommunications. The controllable electrical outlet 350 may be fixedlyattached to the standard electrical outlet 340 via a mounting screw 368(e.g., a “tamper-proof” screw) received through an opening 369 of thestandard electrical outlet 350, for example, to prevent removal or theftof the controllable electrical outlet 350 after installation.

The controllable electrical outlet 350 may additionally or alternativelycomprise upper and lower receptacles 370, 372 located on a side surface374 of the enclosure 352. For example, the upper and lower receptacles370, 372 on the side surface 374 may operate the same as the upper andlower receptacle 354, 356 on the front surface 358, respectively. Inother words, the upper receptacle 370 may be an unswitched receptacleand the lower receptacle 372 may be a switched receptacle. Since theupper and lower receptacles 370, 372 are arranged at a right angle tothe front surface of the standard electrical outlet 340, the upper andlower receptacles 370, 372 on the side surface 374 may accommodateelectrical plugs if there is not much room between the standardelectrical outlet 350 and adjacent furniture. The controllableelectrical outlet 350 may additionally or alternatively comprise one ormore receptacles located on the top surface and/or bottom surface of theenclosure 352.

If one of more of the controllable electrical outlets 300, 320, 350includes a load control circuit for controlling the amount of powerdelivered to the plug-in electrical loads (e.g., a dimmer circuit), therespective electrical outlet may comprise a protrusion at the controlledreceptacle for preventing a standard electrical plug from being pluggedinto the controlled receptacle. Examples of such protrusions forpreventing standard plugs from being plugged into a controlledreceptacle are described in greater detail in commonly-assigned U.S.Pat. No. 7,198,523, issued Apr. 3, 2007, and U.S. Pat. No. 7,311,558,issued Dec. 25, 2007, both entitled RECEPTACLE AND PLUG THEREFOR, theentire disclosures of which are hereby incorporated by reference.

While the controllable electrical outlets 300, 320, 350 shown in FIGS.3A-3C have U.S. style receptacles and/or plugs, the controllableelectrical outlets 300, 320 350 may alternatively or additionally havereceptacles and/or plugs of styles used in other countries. In addition,the controllable electrical outlets 300, 320, 350 could comprise othertypes of receptacles, for example, one or more Universal Serial Bus(USB) connectors, and an internal power supply for charging anelectrical device, such as the battery of a smart phone.

Although the present invention has been described in relation toparticular embodiments thereof, many other variations and modificationsand other uses will become apparent to those skilled in the art. It ispreferred, therefore, that the present invention be limited not by thespecific disclosure herein, but only by the appended claims.

What is claimed is:
 1. A controllable electrical outlet for use in aload control system which also has at least one standard electricaloutlet, the load control system adapted to receive power from a powersource, the controllable electrical outlet comprising: an electricalreceptacle configured to receive a plug of a plug-in electrical load; afirst electrical connection configured to be electrically coupled to thepower source to receive a hot voltage to power the plug-in electricalload; a second electrical connection configured to be electricallycoupled to the standard electrical outlet; a load control circuitelectrically coupled in series between the first and second electricalconnections to control power delivered to the standard electricaloutlet; a communication circuit configured to receive a digital message;and a digital control circuit coupled to the load control circuit andthe communication circuit to control power delivered to the standardelectrical outlet in response to the digital message received via thecommunication circuit.
 2. The controllable electrical outlet of claim 1,wherein the controllable electrical outlet is configured to be mountedto an electrical wallbox.
 3. The controllable electrical outlet of claim2, wherein the communication circuit comprises a wireless communicationcircuit configured to receive the digital message from an input devicevia a wireless signal.
 4. The controllable electrical outlet of claim 3,wherein the digital message received from the input device comprisesinformation regarding an occupancy or vacancy condition in a space inwhich the controllable electrical outlet is installed.
 5. Thecontrollable electrical outlet of claim 3, wherein the digital messagereceived from the input device comprises information regarding anactuation of a button of the input device.
 6. The controllableelectrical outlet of claim 3, further comprising: an actuator configuredto be actuated to associate the controllable electrical outlet with theinput device, the actuator located outside of the electrical wallbox andaccessible to a user when the controllable electrical outlet is mountedto the electrical wallbox.
 7. The controllable electrical outlet ofclaim 1, wherein the load control circuit comprises a switching circuitfor generating a switched-hot voltage.
 8. The controllable electricaloutlet of claim 7, wherein the switched-hot voltage is provided to thesecond electrical connection.
 9. The controllable electrical outlet ofclaim 7, wherein the electrical receptacle is configured to provide thehot voltage to the plug-in electrical load to continuously power theplug-in electrical load.
 10. The controllable electrical outlet of claim7, wherein the electrical receptacle is configured to provide theswitched-hot voltage to the plug-in electrical load, and the digitalcontrol circuit is configured to control the power delivered to theplug-in electrical load in response to the digital message received viathe communication circuit.
 11. The controllable electrical outlet ofclaim 7, wherein the switching circuit comprises a relay having amechanical switch electrically coupled between the first and secondelectrical connections to control power delivered to the standardelectrical outlet, the digital control circuit coupled to an operatingcoil of the relay for opening and closing the mechanical switch of therelay.
 12. The controllable electrical outlet of claim 1, furthercomprising: a first sense circuit electrically coupled in series withthe load control circuit and configured to measure a magnitude of afirst load current conducted through the second electrical connection.13. The controllable electrical outlet of claim 12, further comprising:a third electrical connection adapted to be coupled to a second standardelectrical outlet to provide the hot voltage to the second standardelectrical outlet; and a second sense circuit electrically coupled inseries between the first and second electrical connections andconfigured to measure a magnitude of a second load current conductedthrough the third electrical connection; wherein the digital controlcircuit is configured to transmit an alert if the magnitude of thesecond load current is much greater than the magnitude of the first loadcurrent.
 14. The controllable electrical outlet of claim 12, wherein thedigital control circuit is configured to cause the communication circuitto transmit a digital message including information regarding themagnitude of the first load current measured by the first sense circuit.15. The controllable electrical outlet of claim 12, wherein the digitalcontrol circuit is configured to determine information regarding anoccupancy or vacancy condition in a space in which the controllableelectrical outlet is installed in response to the magnitude of the firstload current.
 16. The controllable electrical outlet of claim 1, furthercomprising: an enclosure having a rear surface; wherein the first andsecond electrical connections comprise first and second plugs arrangedon the rear surface of the enclosure.
 17. The controllable electricaloutlet of claim 16, wherein the electrical receptacle is provided on afront surface or a side surface of the enclosure.
 18. The controllableelectrical outlet of claim 16, wherein the first and second plugs areconfigured to be received in electrical receptacles of a standardelectrical outlet.
 19. The controllable electrical outlet of claim 16,wherein the load control circuit, the communication circuit, and thedigital control circuit are all located inside the enclosure.
 20. Thecontrollable electrical outlet of claim 1, further comprising: a rearenclosure portion; wherein the first and second electrical connectionscomprise screw terminals on the rear enclosure portion.
 21. Thecontrollable electrical outlet of claim 20, wherein the load controlcircuit, the communication circuit, and the digital control circuit areall located inside the rear enclosure portion and the electricalreceptacle is provided on a bezel portion of the controllable electricaloutlet.
 22. The controllable electrical outlet of claim 20, furthercomprising: a front enclosure portion coupled to the rear enclosureportion, the electrical receptacle provided on the front enclosureportion; wherein the load control circuit is located inside the rearenclosure portion, and the communication circuit and the digital controlcircuit are located inside the front enclosure portion.
 23. Thecontrollable electrical outlet of claim 1, wherein the digital controlcircuit is configured to detect that the plug-in electrical load is in astandby mode and to control the load control circuit to disconnect powerfrom the plug-in electrical load in response to receiving the digitalmessage when the plug-in electrical load is in the standby mode.
 24. Thecontrollable electrical outlet of claim 1, wherein the digital controlcircuit is configured to compare an electrical signature of the plug-inelectrical load to one or more electrical signatures stored in a memoryand to cease controlling the power delivered to the plug-in electricalload in response to the digital message if the electrical signature ofthe plug-in electrical load matches one of the electrical signaturesstored in the memory.
 25. A load control system for controlling one ormore plug-in electrical loads adapted to receive power from a powersource, the load control system comprising: a standard electrical outletadapted to receive power from the power source and comprising at leastone electrical receptacle configured to receive a plug of a firstplug-in electrical load; a controllable electrical outlet adapted toreceive power from the power source, the controllable electrical outletcomprising an electrical receptacle configured to receive a plug of asecond plug-in electrical load and an electrical connection configuredto be electrically coupled to the standard electrical outlet; and aninput device configured to transmit a digital message; wherein thecontrollable electrical outlet is configured to control the powerdelivered to the standard electrical outlet in response to the digitalmessage.
 26. The load control system of claim 25, wherein thecontrollable electrical outlet is configured to be mounted to anelectrical wallbox.
 27. The load control system of claim 26, wherein theinput device is configured to wirelessly transmit the digital message toa system controller and the system controller is configured towirelessly transmit a second digital message to the controllableelectrical outlet.
 28. The load control system of claim 26, wherein theinput device is configured to wirelessly transmit the digital messagedirectly to the controllable electrical outlet.
 29. The load controlsystem of claim 28, wherein the controllable electrical outlet isconfigured to receive digital messages directly from the input devicewhen the controllable electrical outlet is associated with the inputdevice.
 30. The load control system of claim 28, further comprising: asystem controller configured to communicate with the controllableelectrical outlet; wherein the controllable electrical outlet isconfigured to control the plug-in electrical load in response to thereceived wireless signal, the controllable electrical outlet configuredto store a type of input device when the controllable electrical outletreceives a wireless signal from the input device, the controllableelectrical outlet configured to transmit to the system controller one ormore digital messages including the type of input device and how thecontrollable electrical outlet controlled the plug-in electrical load inresponse to the wireless signal, the system controller configured todetermine how much energy has been saved as a result of the type ofinput device.
 31. The load control system of claim 30, wherein thecontrollable electrical outlet is configured to transmit a digitalmessage including information regarding a magnitude of load currentmeasured by the controllable electrical outlet to the system controller.32. The load control system of claim 25, wherein the controllableelectrical outlet is configured to measure a magnitude of a load currentconducted through the electrical connection to the standard electricaloutlet.
 33. The load control system of claim 25, further comprising: asystem controller configured to communicate with the controllableelectrical outlet; and wherein the controllable electrical outlet isconfigured to transmit a digital message including information regardingthe magnitude of the load current measured by the controllableelectrical outlet to the system controller.
 34. The load control systemof claim 33, wherein the system controller is configured to determineinformation regarding an occupancy or vacancy condition in a space inwhich the controllable electrical outlet is installed in response to themagnitude of the load current measured by the controllable electricaloutlet.
 35. The load control system of claim 25, wherein thecontrollable electrical outlet is configured to measure a magnitude of afirst load current conducted through one or more switched plug-inelectrical loads and to measure a magnitude of a second load currentconducted through one or more unswitched plug-in electrical loads. 36.The load control system of claim 35, wherein the controllable electricaloutlet is configured to transmit an alert if the magnitude of the secondload current is much greater than the magnitude of the first loadcurrent.
 37. The load control system of claim 35, further comprising: asystem controller configured to communicate with the controllableelectrical outlet; wherein the controllable electrical outlet isconfigured to transmit the magnitudes of the first and second loadcurrents to the system controller, the system controller configured totransmit an alert if the magnitude of the second load current is muchgreater than the magnitude of the first load current.
 38. The loadcontrol system of claim 25, wherein the input device comprises a sensorconfigured to detect an occupancy or vacancy condition in a space inwhich the controllable electrical outlet is installed, and wherein thedigital message transmitted by the input device comprises informationregarding the occupancy or vacancy condition.
 39. The load controlsystem of claim 25, wherein the input device comprises a remote controldevice configured to transmit a digital message in response to anactuation of a button of the remote control device.
 40. The load controlsystem of claim 25, further comprising: a system controller configuredto transmit a control signal to the controllable electrical outlet, thecontrol signal transmitted by the system controller comprising one of: atimeclock command, a load shed command, a demand response command, apeak demand command, or time-of-day pricing information.
 41. Acontrollable electrical outlet for use in a load control system whichalso has at least one standard electrical outlet, the load controlsystem adapted to receive power from a power source, the controllableelectrical outlet comprising: a line-side hot connection and a line-sideneutral electrical connection connectable the power source to receive ahot voltage to power the plug-in electrical load; an electricalreceptacle having a first load-side hot electrical connection and afirst load-side neutral electrical connection configured to beelectrically connected to respective prongs of a plug of a plug-inelectrical load; a second load-side hot electrical connectionconnectable to the standard electrical outlet; a load control circuitelectrically coupled in series between the first and second electricalconnections to control power delivered to the standard electricaloutlet; a communication circuit configured to receive a digital message;and a digital control circuit coupled to the load control circuit andthe communication circuit to control power delivered to the standardelectrical outlet in response to the digital message received via thecommunication circuit.